arch/x86/mm/init_64.c

   1 /*
   2  *  linux/arch/x86_64/mm/init.c
   3  *
   4  *  Copyright (C) 1995  Linus Torvalds
   5  *  Copyright (C) 2000  Pavel Machek <pavel@suse.cz>
   6  *  Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
   7  */
   8
   9 #include <linux/signal.h>
  10 #include <linux/sched.h>
  11 #include <linux/kernel.h>
  12 #include <linux/errno.h>
  13 #include <linux/string.h>
  14 #include <linux/types.h>
  15 #include <linux/ptrace.h>
  16 #include <linux/mman.h>
  17 #include <linux/mm.h>
  18 #include <linux/swap.h>
  19 #include <linux/smp.h>
  20 #include <linux/init.h>
  21 #include <linux/initrd.h>
  22 #include <linux/pagemap.h>
  23 #include <linux/bootmem.h>
  24 #include <linux/proc_fs.h>
  25 #include <linux/pci.h>
  26 #include <linux/pfn.h>
  27 #include <linux/poison.h>
  28 #include <linux/dma-mapping.h>
  29 #include <linux/module.h>
  30 #include <linux/memory_hotplug.h>
  31 #include <linux/nmi.h>
  32
  33 #include <asm/processor.h>
  34 #include <asm/system.h>
  35 #include <asm/uaccess.h>
  36 #include <asm/pgtable.h>
  37 #include <asm/pgalloc.h>
  38 #include <asm/dma.h>
  39 #include <asm/fixmap.h>
  40 #include <asm/e820.h>
  41 #include <asm/apic.h>
  42 #include <asm/tlb.h>
  43 #include <asm/mmu_context.h>
  44 #include <asm/proto.h>
  45 #include <asm/smp.h>
  46 #include <asm/sections.h>
  47 #include <asm/kdebug.h>
  48 #include <asm/numa.h>
  49 #include <asm/cacheflush.h>
  50
  51 /*
  52  * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
  53  * The direct mapping extends to max_pfn_mapped, so that we can directly access
  54  * apertures, ACPI and other tables without having to play with fixmaps.
  55  */
  56 unsigned long max_low_pfn_mapped;
  57 unsigned long max_pfn_mapped;
  58
  59 static unsigned long dma_reserve __initdata;
  60
  61 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  62
  63 int direct_gbpages
  64 #ifdef CONFIG_DIRECT_GBPAGES
  65                                 = 1
  66 #endif
  67 ;
  68
  69 static int __init parse_direct_gbpages_off(char *arg)
  70 {
  71         direct_gbpages = 0;
  72         return 0;
  73 }
  74 early_param("nogbpages", parse_direct_gbpages_off);
  75
  76 static int __init parse_direct_gbpages_on(char *arg)
  77 {
  78         direct_gbpages = 1;
  79         return 0;
  80 }
  81 early_param("gbpages", parse_direct_gbpages_on);
  82
  83 /*
  84  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
  85  * physical space so we can cache the place of the first one and move
  86  * around without checking the pgd every time.
  87  */
  88
  89 int after_bootmem;
  90
  91 /*
  92  * NOTE: This function is marked __ref because it calls __init function
  93  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
  94  */
  95 static __ref void *spp_getpage(void)
  96 {
  97         void *ptr;
  98
  99         if (after_bootmem)
 100                 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
 101         else
 102                 ptr = alloc_bootmem_pages(PAGE_SIZE);
 103
 104         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
 105                 panic("set_pte_phys: cannot allocate page data %s\n",
 106                         after_bootmem ? "after bootmem" : "");
 107         }
 108
 109         pr_debug("spp_getpage %p\n", ptr);
 110
 111         return ptr;
 112 }
 113
 114 void
 115 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
 116 {
 117         pud_t *pud;
 118         pmd_t *pmd;
 119         pte_t *pte;
 120
 121         pud = pud_page + pud_index(vaddr);
 122         if (pud_none(*pud)) {
 123                 pmd = (pmd_t *) spp_getpage();
 124                 pud_populate(&init_mm, pud, pmd);
 125                 if (pmd != pmd_offset(pud, 0)) {
 126                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
 127                                 pmd, pmd_offset(pud, 0));
 128                         return;
 129                 }
 130         }
 131         pmd = pmd_offset(pud, vaddr);
 132         if (pmd_none(*pmd)) {
 133                 pte = (pte_t *) spp_getpage();
 134                 pmd_populate_kernel(&init_mm, pmd, pte);
 135                 if (pte != pte_offset_kernel(pmd, 0)) {
 136                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
 137                         return;
 138                 }
 139         }
 140
 141         pte = pte_offset_kernel(pmd, vaddr);
 142         if (!pte_none(*pte) && pte_val(new_pte) &&
 143             pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
 144                 pte_ERROR(*pte);
 145         set_pte(pte, new_pte);
 146
 147         /*
 148          * It's enough to flush this one mapping.
 149          * (PGE mappings get flushed as well)
 150          */
 151         __flush_tlb_one(vaddr);
 152 }
 153
 154 void
 155 set_pte_vaddr(unsigned long vaddr, pte_t pteval)
 156 {
 157         pgd_t *pgd;
 158         pud_t *pud_page;
 159
 160         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
 161
 162         pgd = pgd_offset_k(vaddr);
 163         if (pgd_none(*pgd)) {
 164                 printk(KERN_ERR
 165                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
 166                 return;
 167         }
 168         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
 169         set_pte_vaddr_pud(pud_page, vaddr, pteval);
 170 }
 171
 172 /*
 173  * Create large page table mappings for a range of physical addresses.
 174  */
 175 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
 176                                                 pgprot_t prot)
 177 {
 178         pgd_t *pgd;
 179         pud_t *pud;
 180         pmd_t *pmd;
 181
 182         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
 183         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
 184                 pgd = pgd_offset_k((unsigned long)__va(phys));
 185                 if (pgd_none(*pgd)) {
 186                         pud = (pud_t *) spp_getpage();
 187                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
 188                                                 _PAGE_USER));
 189                 }
 190                 pud = pud_offset(pgd, (unsigned long)__va(phys));
 191                 if (pud_none(*pud)) {
 192                         pmd = (pmd_t *) spp_getpage();
 193                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
 194                                                 _PAGE_USER));
 195                 }
 196                 pmd = pmd_offset(pud, phys);
 197                 BUG_ON(!pmd_none(*pmd));
 198                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
 199         }
 200 }
 201
 202 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
 203 {
 204         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
 205 }
 206
 207 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
 208 {
 209         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
 210 }
 211
 212 /*
 213  * The head.S code sets up the kernel high mapping:
 214  *
 215  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
 216  *
 217  * phys_addr holds the negative offset to the kernel, which is added
 218  * to the compile time generated pmds. This results in invalid pmds up
 219  * to the point where we hit the physaddr 0 mapping.
 220  *
 221  * We limit the mappings to the region from _text to _end.  _end is
 222  * rounded up to the 2MB boundary. This catches the invalid pmds as
 223  * well, as they are located before _text:
 224  */
 225 void __init cleanup_highmap(void)
 226 {
 227         unsigned long vaddr = __START_KERNEL_map;
 228         unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
 229         pmd_t *pmd = level2_kernel_pgt;
 230         pmd_t *last_pmd = pmd + PTRS_PER_PMD;
 231
 232         for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
 233                 if (pmd_none(*pmd))
 234                         continue;
 235                 if (vaddr < (unsigned long) _text || vaddr > end)
 236                         set_pmd(pmd, __pmd(0));
 237         }
 238 }
 239
 240 static unsigned long __initdata table_start;
 241 static unsigned long __meminitdata table_end;
 242 static unsigned long __meminitdata table_top;
 243
 244 static __ref void *alloc_low_page(unsigned long *phys)
 245 {
 246         unsigned long pfn = table_end++;
 247         void *adr;
 248
 249         if (after_bootmem) {
 250                 adr = (void *)get_zeroed_page(GFP_ATOMIC);
 251                 *phys = __pa(adr);
 252
 253                 return adr;
 254         }
 255
 256         if (pfn >= table_top)
 257                 panic("alloc_low_page: ran out of memory");
 258
 259         adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
 260         memset(adr, 0, PAGE_SIZE);
 261         *phys  = pfn * PAGE_SIZE;
 262         return adr;
 263 }
 264
 265 static __ref void unmap_low_page(void *adr)
 266 {
 267         if (after_bootmem)
 268                 return;
 269
 270         early_iounmap(adr, PAGE_SIZE);
 271 }
 272
 273 static unsigned long __meminit
 274 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
 275               pgprot_t prot)
 276 {
 277         unsigned pages = 0;
 278         unsigned long last_map_addr = end;
 279         int i;
 280
 281         pte_t *pte = pte_page + pte_index(addr);
 282
 283         for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
 284
 285                 if (addr >= end) {
 286                         if (!after_bootmem) {
 287                                 for(; i < PTRS_PER_PTE; i++, pte++)
 288                                         set_pte(pte, __pte(0));
 289                         }
 290                         break;
 291                 }
 292
 293                 /*
 294                  * We will re-use the existing mapping.
 295                  * Xen for example has some special requirements, like mapping
 296                  * pagetable pages as RO. So assume someone who pre-setup
 297                  * these mappings are more intelligent.
 298                  */
 299                 if (pte_val(*pte))
 300                         continue;
 301
 302                 if (0)
 303                         printk("   pte=%p addr=%lx pte=%016lx\n",
 304                                pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
 305                 pages++;
 306                 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
 307                 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
 308         }
 309
 310         update_page_count(PG_LEVEL_4K, pages);
 311
 312         return last_map_addr;
 313 }
 314
 315 static unsigned long __meminit
 316 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
 317                 pgprot_t prot)
 318 {
 319         pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
 320
 321         return phys_pte_init(pte, address, end, prot);
 322 }
 323
 324 static unsigned long __meminit
 325 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
 326               unsigned long page_size_mask, pgprot_t prot)
 327 {
 328         unsigned long pages = 0;
 329         unsigned long last_map_addr = end;
 330
 331         int i = pmd_index(address);
 332
 333         for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
 334                 unsigned long pte_phys;
 335                 pmd_t *pmd = pmd_page + pmd_index(address);
 336                 pte_t *pte;
 337                 pgprot_t new_prot = prot;
 338
 339                 if (address >= end) {
 340                         if (!after_bootmem) {
 341                                 for (; i < PTRS_PER_PMD; i++, pmd++)
 342                                         set_pmd(pmd, __pmd(0));
 343                         }
 344                         break;
 345                 }
 346
 347                 if (pmd_val(*pmd)) {
 348                         if (!pmd_large(*pmd)) {
 349                                 spin_lock(&init_mm.page_table_lock);
 350                                 last_map_addr = phys_pte_update(pmd, address,
 351                                                                 end, prot);
 352                                 spin_unlock(&init_mm.page_table_lock);
 353                                 continue;
 354                         }
 355                         /*
 356                          * If we are ok with PG_LEVEL_2M mapping, then we will
 357                          * use the existing mapping,
 358                          *
 359                          * Otherwise, we will split the large page mapping but
 360                          * use the same existing protection bits except for
 361                          * large page, so that we don't violate Intel's TLB
 362                          * Application note (317080) which says, while changing
 363                          * the page sizes, new and old translations should
 364                          * not differ with respect to page frame and
 365                          * attributes.
 366                          */
 367                         if (page_size_mask & (1 << PG_LEVEL_2M))
 368                                 continue;
 369                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
 370                 }
 371
 372                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
 373                         pages++;
 374                         spin_lock(&init_mm.page_table_lock);
 375                         set_pte((pte_t *)pmd,
 376                                 pfn_pte(address >> PAGE_SHIFT,
 377                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
 378                         spin_unlock(&init_mm.page_table_lock);
 379                         last_map_addr = (address & PMD_MASK) + PMD_SIZE;
 380                         continue;
 381                 }
 382
 383                 pte = alloc_low_page(&pte_phys);
 384                 last_map_addr = phys_pte_init(pte, address, end, new_prot);
 385                 unmap_low_page(pte);
 386
 387                 spin_lock(&init_mm.page_table_lock);
 388                 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
 389                 spin_unlock(&init_mm.page_table_lock);
 390         }
 391         update_page_count(PG_LEVEL_2M, pages);
 392         return last_map_addr;
 393 }
 394
 395 static unsigned long __meminit
 396 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
 397                 unsigned long page_size_mask, pgprot_t prot)
 398 {
 399         pmd_t *pmd = pmd_offset(pud, 0);
 400         unsigned long last_map_addr;
 401
 402         last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
 403         __flush_tlb_all();
 404         return last_map_addr;
 405 }
 406
 407 static unsigned long __meminit
 408 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
 409                          unsigned long page_size_mask)
 410 {
 411         unsigned long pages = 0;
 412         unsigned long last_map_addr = end;
 413         int i = pud_index(addr);
 414
 415         for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
 416                 unsigned long pmd_phys;
 417                 pud_t *pud = pud_page + pud_index(addr);
 418                 pmd_t *pmd;
 419                 pgprot_t prot = PAGE_KERNEL;
 420
 421                 if (addr >= end)
 422                         break;
 423
 424                 if (!after_bootmem &&
 425                                 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
 426                         set_pud(pud, __pud(0));
 427                         continue;
 428                 }
 429
 430                 if (pud_val(*pud)) {
 431                         if (!pud_large(*pud)) {
 432                                 last_map_addr = phys_pmd_update(pud, addr, end,
 433                                                          page_size_mask, prot);
 434                                 continue;
 435                         }
 436                         /*
 437                          * If we are ok with PG_LEVEL_1G mapping, then we will
 438                          * use the existing mapping.
 439                          *
 440                          * Otherwise, we will split the gbpage mapping but use
 441                          * the same existing protection  bits except for large
 442                          * page, so that we don't violate Intel's TLB
 443                          * Application note (317080) which says, while changing
 444                          * the page sizes, new and old translations should
 445                          * not differ with respect to page frame and
 446                          * attributes.
 447                          */
 448                         if (page_size_mask & (1 << PG_LEVEL_1G))
 449                                 continue;
 450                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
 451                 }
 452
 453                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
 454                         pages++;
 455                         spin_lock(&init_mm.page_table_lock);
 456                         set_pte((pte_t *)pud,
 457                                 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
 458                         spin_unlock(&init_mm.page_table_lock);
 459                         last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
 460                         continue;
 461                 }
 462
 463                 pmd = alloc_low_page(&pmd_phys);
 464                 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
 465                                               prot);
 466                 unmap_low_page(pmd);
 467
 468                 spin_lock(&init_mm.page_table_lock);
 469                 pud_populate(&init_mm, pud, __va(pmd_phys));
 470                 spin_unlock(&init_mm.page_table_lock);
 471         }
 472         __flush_tlb_all();
 473
 474         update_page_count(PG_LEVEL_1G, pages);
 475
 476         return last_map_addr;
 477 }
 478
 479 static unsigned long __meminit
 480 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
 481                  unsigned long page_size_mask)
 482 {
 483         pud_t *pud;
 484
 485         pud = (pud_t *)pgd_page_vaddr(*pgd);
 486
 487         return phys_pud_init(pud, addr, end, page_size_mask);
 488 }
 489
 490 static void __init find_early_table_space(unsigned long end, int use_pse,
 491                                           int use_gbpages)
 492 {
 493         unsigned long puds, pmds, ptes, tables, start;
 494
 495         puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
 496         tables = round_up(puds * sizeof(pud_t), PAGE_SIZE);
 497         if (use_gbpages) {
 498                 unsigned long extra;
 499                 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
 500                 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
 501         } else
 502                 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
 503         tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
 504
 505         if (use_pse) {
 506                 unsigned long extra;
 507                 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
 508                 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
 509         } else
 510                 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
 511         tables += round_up(ptes * sizeof(pte_t), PAGE_SIZE);
 512
 513         /*
 514          * RED-PEN putting page tables only on node 0 could
 515          * cause a hotspot and fill up ZONE_DMA. The page tables
 516          * need roughly 0.5KB per GB.
 517          */
 518         start = 0x8000;
 519         table_start = find_e820_area(start, end, tables, PAGE_SIZE);
 520         if (table_start == -1UL)
 521                 panic("Cannot find space for the kernel page tables");
 522
 523         table_start >>= PAGE_SHIFT;
 524         table_end = table_start;
 525         table_top = table_start + (tables >> PAGE_SHIFT);
 526
 527         printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
 528                 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
 529 }
 530
 531 static void __init init_gbpages(void)
 532 {
 533         if (direct_gbpages && cpu_has_gbpages)
 534                 printk(KERN_INFO "Using GB pages for direct mapping\n");
 535         else
 536                 direct_gbpages = 0;
 537 }
 538
 539 static unsigned long __init kernel_physical_mapping_init(unsigned long start,
 540                                                 unsigned long end,
 541                                                 unsigned long page_size_mask)
 542 {
 543
 544         unsigned long next, last_map_addr = end;
 545
 546         start = (unsigned long)__va(start);
 547         end = (unsigned long)__va(end);
 548
 549         for (; start < end; start = next) {
 550                 pgd_t *pgd = pgd_offset_k(start);
 551                 unsigned long pud_phys;
 552                 pud_t *pud;
 553
 554                 next = (start + PGDIR_SIZE) & PGDIR_MASK;
 555                 if (next > end)
 556                         next = end;
 557
 558                 if (pgd_val(*pgd)) {
 559                         last_map_addr = phys_pud_update(pgd, __pa(start),
 560                                                  __pa(end), page_size_mask);
 561                         continue;
 562                 }
 563
 564                 pud = alloc_low_page(&pud_phys);
 565                 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
 566                                                  page_size_mask);
 567                 unmap_low_page(pud);
 568
 569                 spin_lock(&init_mm.page_table_lock);
 570                 pgd_populate(&init_mm, pgd, __va(pud_phys));
 571                 spin_unlock(&init_mm.page_table_lock);
 572         }
 573         __flush_tlb_all();
 574
 575         return last_map_addr;
 576 }
 577
 578 struct map_range {
 579         unsigned long start;
 580         unsigned long end;
 581         unsigned page_size_mask;
 582 };
 583
 584 #define NR_RANGE_MR 5
 585
 586 static int save_mr(struct map_range *mr, int nr_range,
 587                    unsigned long start_pfn, unsigned long end_pfn,
 588                    unsigned long page_size_mask)
 589 {
 590
 591         if (start_pfn < end_pfn) {
 592                 if (nr_range >= NR_RANGE_MR)
 593                         panic("run out of range for init_memory_mapping\n");
 594                 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
 595                 mr[nr_range].end   = end_pfn<<PAGE_SHIFT;
 596                 mr[nr_range].page_size_mask = page_size_mask;
 597                 nr_range++;
 598         }
 599
 600         return nr_range;
 601 }
 602
 603 /*
 604  * Setup the direct mapping of the physical memory at PAGE_OFFSET.
 605  * This runs before bootmem is initialized and gets pages directly from
 606  * the physical memory. To access them they are temporarily mapped.
 607  */
 608 unsigned long __init_refok init_memory_mapping(unsigned long start,
 609                                                unsigned long end)
 610 {
 611         unsigned long last_map_addr = 0;
 612         unsigned long page_size_mask = 0;
 613         unsigned long start_pfn, end_pfn;
 614
 615         struct map_range mr[NR_RANGE_MR];
 616         int nr_range, i;
 617         int use_pse, use_gbpages;
 618
 619         printk(KERN_INFO "init_memory_mapping\n");
 620
 621         /*
 622          * Find space for the kernel direct mapping tables.
 623          *
 624          * Later we should allocate these tables in the local node of the
 625          * memory mapped. Unfortunately this is done currently before the
 626          * nodes are discovered.
 627          */
 628         if (!after_bootmem)
 629                 init_gbpages();
 630
 631 #ifdef CONFIG_DEBUG_PAGEALLOC
 632         /*
 633          * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
 634          * This will simplify cpa(), which otherwise needs to support splitting
 635          * large pages into small in interrupt context, etc.
 636          */
 637         use_pse = use_gbpages = 0;
 638 #else
 639         use_pse = cpu_has_pse;
 640         use_gbpages = direct_gbpages;
 641 #endif
 642
 643         if (use_gbpages)
 644                 page_size_mask |= 1 << PG_LEVEL_1G;
 645         if (use_pse)
 646                 page_size_mask |= 1 << PG_LEVEL_2M;
 647
 648         memset(mr, 0, sizeof(mr));
 649         nr_range = 0;
 650
 651         /* head if not big page alignment ?*/
 652         start_pfn = start >> PAGE_SHIFT;
 653         end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
 654                         << (PMD_SHIFT - PAGE_SHIFT);
 655         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
 656
 657         /* big page (2M) range*/
 658         start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
 659                          << (PMD_SHIFT - PAGE_SHIFT);
 660         end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
 661                          << (PUD_SHIFT - PAGE_SHIFT);
 662         if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
 663                 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
 664         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
 665                         page_size_mask & (1<<PG_LEVEL_2M));
 666
 667         /* big page (1G) range */
 668         start_pfn = end_pfn;
 669         end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
 670         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
 671                                 page_size_mask &
 672                                  ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
 673
 674         /* tail is not big page (1G) alignment */
 675         start_pfn = end_pfn;
 676         end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
 677         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
 678                         page_size_mask & (1<<PG_LEVEL_2M));
 679
 680         /* tail is not big page (2M) alignment */
 681         start_pfn = end_pfn;
 682         end_pfn = end>>PAGE_SHIFT;
 683         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
 684
 685         /* try to merge same page size and continuous */
 686         for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
 687                 unsigned long old_start;
 688                 if (mr[i].end != mr[i+1].start ||
 689                     mr[i].page_size_mask != mr[i+1].page_size_mask)
 690                         continue;
 691                 /* move it */
 692                 old_start = mr[i].start;
 693                 memmove(&mr[i], &mr[i+1],
 694                          (nr_range - 1 - i) * sizeof (struct map_range));
 695                 mr[i].start = old_start;
 696                 nr_range--;
 697         }
 698
 699         for (i = 0; i < nr_range; i++)
 700                 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
 701                                 mr[i].start, mr[i].end,
 702                         (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
 703                          (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
 704
 705         if (!after_bootmem)
 706                 find_early_table_space(end, use_pse, use_gbpages);
 707
 708         for (i = 0; i < nr_range; i++)
 709                 last_map_addr = kernel_physical_mapping_init(
 710                                         mr[i].start, mr[i].end,
 711                                         mr[i].page_size_mask);
 712
 713         if (!after_bootmem)
 714                 mmu_cr4_features = read_cr4();
 715         __flush_tlb_all();
 716
 717         if (!after_bootmem && table_end > table_start)
 718                 reserve_early(table_start << PAGE_SHIFT,
 719                                  table_end << PAGE_SHIFT, "PGTABLE");
 720
 721         printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
 722                          last_map_addr, end);
 723
 724         if (!after_bootmem)
 725                 early_memtest(start, end);
 726
 727         return last_map_addr >> PAGE_SHIFT;
 728 }
 729
 730 #ifndef CONFIG_NUMA
 731 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
 732 {
 733         unsigned long bootmap_size, bootmap;
 734
 735         bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
 736         bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
 737                                  PAGE_SIZE);
 738         if (bootmap == -1L)
 739                 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
 740         /* don't touch min_low_pfn */
 741         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
 742                                          0, end_pfn);
 743         e820_register_active_regions(0, start_pfn, end_pfn);
 744         free_bootmem_with_active_regions(0, end_pfn);
 745         early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
 746         reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
 747 }
 748
 749 void __init paging_init(void)
 750 {
 751         unsigned long max_zone_pfns[MAX_NR_ZONES];
 752
 753         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 754         max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
 755         max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
 756         max_zone_pfns[ZONE_NORMAL] = max_pfn;
 757
 758         memory_present(0, 0, max_pfn);
 759         sparse_init();
 760         free_area_init_nodes(max_zone_pfns);
 761 }
 762 #endif
 763
 764 /*
 765  * Memory hotplug specific functions
 766  */
 767 #ifdef CONFIG_MEMORY_HOTPLUG
 768 /*
 769  * Memory is added always to NORMAL zone. This means you will never get
 770  * additional DMA/DMA32 memory.
 771  */
 772 int arch_add_memory(int nid, u64 start, u64 size)
 773 {
 774         struct pglist_data *pgdat = NODE_DATA(nid);
 775         struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
 776         unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
 777         unsigned long nr_pages = size >> PAGE_SHIFT;
 778         int ret;
 779
 780         last_mapped_pfn = init_memory_mapping(start, start + size-1);
 781         if (last_mapped_pfn > max_pfn_mapped)
 782                 max_pfn_mapped = last_mapped_pfn;
 783
 784         ret = __add_pages(zone, start_pfn, nr_pages);
 785         WARN_ON(1);
 786
 787         return ret;
 788 }
 789 EXPORT_SYMBOL_GPL(arch_add_memory);
 790
 791 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
 792 int memory_add_physaddr_to_nid(u64 start)
 793 {
 794         return 0;
 795 }
 796 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 797 #endif
 798
 799 #endif /* CONFIG_MEMORY_HOTPLUG */
 800
 801 /*
 802  * devmem_is_allowed() checks to see if /dev/mem access to a certain address
 803  * is valid. The argument is a physical page number.
 804  *
 805  *
 806  * On x86, access has to be given to the first megabyte of ram because that area
 807  * contains bios code and data regions used by X and dosemu and similar apps.
 808  * Access has to be given to non-kernel-ram areas as well, these contain the PCI
 809  * mmio resources as well as potential bios/acpi data regions.
 810  */
 811 int devmem_is_allowed(unsigned long pagenr)
 812 {
 813         if (pagenr <= 256)
 814                 return 1;
 815         if (!page_is_ram(pagenr))
 816                 return 1;
 817         return 0;
 818 }
 819
 820
 821 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
 822                          kcore_modules, kcore_vsyscall;
 823
 824 void __init mem_init(void)
 825 {
 826         long codesize, reservedpages, datasize, initsize;
 827
 828         pci_iommu_alloc();
 829
 830         /* clear_bss() already clear the empty_zero_page */
 831
 832         reservedpages = 0;
 833
 834         /* this will put all low memory onto the freelists */
 835 #ifdef CONFIG_NUMA
 836         totalram_pages = numa_free_all_bootmem();
 837 #else
 838         totalram_pages = free_all_bootmem();
 839 #endif
 840         reservedpages = max_pfn - totalram_pages -
 841                                         absent_pages_in_range(0, max_pfn);
 842         after_bootmem = 1;
 843
 844         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 845         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 846         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 847
 848         /* Register memory areas for /proc/kcore */
 849         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 850         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 851                    VMALLOC_END-VMALLOC_START);
 852         kclist_add(&kcore_kernel, &_stext, _end - _stext);
 853         kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
 854         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
 855                                  VSYSCALL_END - VSYSCALL_START);
 856
 857         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 858                                 "%ldk reserved, %ldk data, %ldk init)\n",
 859                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 860                 max_pfn << (PAGE_SHIFT-10),
 861                 codesize >> 10,
 862                 reservedpages << (PAGE_SHIFT-10),
 863                 datasize >> 10,
 864                 initsize >> 10);
 865 }
 866
 867 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 868 {
 869         unsigned long addr = begin;
 870
 871         if (addr >= end)
 872                 return;
 873
 874         /*
 875          * If debugging page accesses then do not free this memory but
 876          * mark them not present - any buggy init-section access will
 877          * create a kernel page fault:
 878          */
 879 #ifdef CONFIG_DEBUG_PAGEALLOC
 880         printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
 881                 begin, PAGE_ALIGN(end));
 882         set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
 883 #else
 884         printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
 885
 886         for (; addr < end; addr += PAGE_SIZE) {
 887                 ClearPageReserved(virt_to_page(addr));
 888                 init_page_count(virt_to_page(addr));
 889                 memset((void *)(addr & ~(PAGE_SIZE-1)),
 890                         POISON_FREE_INITMEM, PAGE_SIZE);
 891                 free_page(addr);
 892                 totalram_pages++;
 893         }
 894 #endif
 895 }
 896
 897 void free_initmem(void)
 898 {
 899         free_init_pages("unused kernel memory",
 900                         (unsigned long)(&__init_begin),
 901                         (unsigned long)(&__init_end));
 902 }
 903
 904 #ifdef CONFIG_DEBUG_RODATA
 905 const int rodata_test_data = 0xC3;
 906 EXPORT_SYMBOL_GPL(rodata_test_data);
 907
 908 void mark_rodata_ro(void)
 909 {
 910         unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
 911         unsigned long rodata_start =
 912                 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
 913
 914 #ifdef CONFIG_DYNAMIC_FTRACE
 915         /* Dynamic tracing modifies the kernel text section */
 916         start = rodata_start;
 917 #endif
 918
 919         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
 920                (end - start) >> 10);
 921         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
 922
 923         /*
 924          * The rodata section (but not the kernel text!) should also be
 925          * not-executable.
 926          */
 927         set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
 928
 929         rodata_test();
 930
 931 #ifdef CONFIG_CPA_DEBUG
 932         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
 933         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
 934
 935         printk(KERN_INFO "Testing CPA: again\n");
 936         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
 937 #endif
 938 }
 939
 940 #endif
 941
 942 #ifdef CONFIG_BLK_DEV_INITRD
 943 void free_initrd_mem(unsigned long start, unsigned long end)
 944 {
 945         free_init_pages("initrd memory", start, end);
 946 }
 947 #endif
 948
 949 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
 950                                    int flags)
 951 {
 952 #ifdef CONFIG_NUMA
 953         int nid, next_nid;
 954         int ret;
 955 #endif
 956         unsigned long pfn = phys >> PAGE_SHIFT;
 957
 958         if (pfn >= max_pfn) {
 959                 /*
 960                  * This can happen with kdump kernels when accessing
 961                  * firmware tables:
 962                  */
 963                 if (pfn < max_pfn_mapped)
 964                         return -EFAULT;
 965
 966                 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
 967                                 phys, len);
 968                 return -EFAULT;
 969         }
 970
 971         /* Should check here against the e820 map to avoid double free */
 972 #ifdef CONFIG_NUMA
 973         nid = phys_to_nid(phys);
 974         next_nid = phys_to_nid(phys + len - 1);
 975         if (nid == next_nid)
 976                 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
 977         else
 978                 ret = reserve_bootmem(phys, len, flags);
 979
 980         if (ret != 0)
 981                 return ret;
 982
 983 #else
 984         reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
 985 #endif
 986
 987         if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
 988                 dma_reserve += len / PAGE_SIZE;
 989                 set_dma_reserve(dma_reserve);
 990         }
 991
 992         return 0;
 993 }
 994
 995 int kern_addr_valid(unsigned long addr)
 996 {
 997         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
 998         pgd_t *pgd;
 999         pud_t *pud;
1000         pmd_t *pmd;
1001         pte_t *pte;
1002
1003         if (above != 0 && above != -1UL)
1004                 return 0;
1005
1006         pgd = pgd_offset_k(addr);
1007         if (pgd_none(*pgd))
1008                 return 0;
1009
1010         pud = pud_offset(pgd, addr);
1011         if (pud_none(*pud))
1012                 return 0;
1013
1014         pmd = pmd_offset(pud, addr);
1015         if (pmd_none(*pmd))
1016                 return 0;
1017
1018         if (pmd_large(*pmd))
1019                 return pfn_valid(pmd_pfn(*pmd));
1020
1021         pte = pte_offset_kernel(pmd, addr);
1022         if (pte_none(*pte))
1023                 return 0;
1024
1025         return pfn_valid(pte_pfn(*pte));
1026 }
1027
1028 /*
1029  * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
1030  * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1031  * not need special handling anymore:
1032  */
1033 static struct vm_area_struct gate_vma = {
1034         .vm_start       = VSYSCALL_START,
1035         .vm_end         = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
1036         .vm_page_prot   = PAGE_READONLY_EXEC,
1037         .vm_flags       = VM_READ | VM_EXEC
1038 };
1039
1040 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
1041 {
1042 #ifdef CONFIG_IA32_EMULATION
1043         if (test_tsk_thread_flag(tsk, TIF_IA32))
1044                 return NULL;
1045 #endif
1046         return &gate_vma;
1047 }
1048
1049 int in_gate_area(struct task_struct *task, unsigned long addr)
1050 {
1051         struct vm_area_struct *vma = get_gate_vma(task);
1052
1053         if (!vma)
1054                 return 0;
1055
1056         return (addr >= vma->vm_start) && (addr < vma->vm_end);
1057 }
1058
1059 /*
1060  * Use this when you have no reliable task/vma, typically from interrupt
1061  * context. It is less reliable than using the task's vma and may give
1062  * false positives:
1063  */
1064 int in_gate_area_no_task(unsigned long addr)
1065 {
1066         return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1067 }
1068
1069 const char *arch_vma_name(struct vm_area_struct *vma)
1070 {
1071         if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1072                 return "[vdso]";
1073         if (vma == &gate_vma)
1074                 return "[vsyscall]";
1075         return NULL;
1076 }
1077
1078 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1079 /*
1080  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1081  */
1082 static long __meminitdata addr_start, addr_end;
1083 static void __meminitdata *p_start, *p_end;
1084 static int __meminitdata node_start;
1085
1086 int __meminit
1087 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1088 {
1089         unsigned long addr = (unsigned long)start_page;
1090         unsigned long end = (unsigned long)(start_page + size);
1091         unsigned long next;
1092         pgd_t *pgd;
1093         pud_t *pud;
1094         pmd_t *pmd;
1095
1096         for (; addr < end; addr = next) {
1097                 void *p = NULL;
1098
1099                 pgd = vmemmap_pgd_populate(addr, node);
1100                 if (!pgd)
1101                         return -ENOMEM;
1102
1103                 pud = vmemmap_pud_populate(pgd, addr, node);
1104                 if (!pud)
1105                         return -ENOMEM;
1106
1107                 if (!cpu_has_pse) {
1108                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1109                         pmd = vmemmap_pmd_populate(pud, addr, node);
1110
1111                         if (!pmd)
1112                                 return -ENOMEM;
1113
1114                         p = vmemmap_pte_populate(pmd, addr, node);
1115
1116                         if (!p)
1117                                 return -ENOMEM;
1118
1119                         addr_end = addr + PAGE_SIZE;
1120                         p_end = p + PAGE_SIZE;
1121                 } else {
1122                         next = pmd_addr_end(addr, end);
1123
1124                         pmd = pmd_offset(pud, addr);
1125                         if (pmd_none(*pmd)) {
1126                                 pte_t entry;
1127
1128                                 p = vmemmap_alloc_block(PMD_SIZE, node);
1129                                 if (!p)
1130                                         return -ENOMEM;
1131
1132                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1133                                                 PAGE_KERNEL_LARGE);
1134                                 set_pmd(pmd, __pmd(pte_val(entry)));
1135
1136                                 /* check to see if we have contiguous blocks */
1137                                 if (p_end != p || node_start != node) {
1138                                         if (p_start)
1139                                                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1140                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1141                                         addr_start = addr;
1142                                         node_start = node;
1143                                         p_start = p;
1144                                 }
1145
1146                                 addr_end = addr + PMD_SIZE;
1147                                 p_end = p + PMD_SIZE;
1148                         } else
1149                                 vmemmap_verify((pte_t *)pmd, node, addr, next);
1150                 }
1151
1152         }
1153         return 0;
1154 }
1155
1156 void __meminit vmemmap_populate_print_last(void)
1157 {
1158         if (p_start) {
1159                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1160                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1161                 p_start = NULL;
1162                 p_end = NULL;
1163                 node_start = 0;
1164         }
1165 }
1166 #endif